Sun, which has always been persnickety and hysterically protectionist about its Java compatibility tests, said Thursday that it was putting "write one, run anywhere" certification in the hands of the community with the release of an OpenJDK Community Technology Compatibility Kit License.

It called it "another milestone in the release of Java technology as open source software" - although you have to be part of Sun's OpenJDK to qualify - and said it wants "free Java technology implementations available in GNU/Linux distributions everywhere."

The license is to the Java Compatibility Kit (JCK), a suite of tests, tools and documentation that determines whether an implementation complies or not with the Java Platform Standard Edition 6 specification.

Java licensees once had to fight to get access to the tests and until now you had to be a licensee to run them. The Apache Harmony project to build a rival Java Standard Edition still doesn't qualify and the compatibility tests hobble forking.

Sun claims open source Java implementations will be boosted if they can be certified as compatible.

It also says that the JCK license terms "will permit contributors to fully comply with the terms of the GNU General Public License version 2" - 2, note, not 3.

If you pass you get to use the "Java compatible" trademark and logo.

Sun hasn't been able to open source all of Java because of third-party encumbrances,

See http://openjdk.java.net/legal/openjdk-tck-license.pdf.

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